Treating hydrocarbon oils with inert solids and gaseous halogen containing compounds



Nov. 4, 1958 c, ADAMS ETAL 2,859,174

TREATING HYDROCARBON OILS WITH INERT SOLIDS AND GASEOUS HALOGEN CONTAINING COMPOUNDS Filed April 29, 1952 as s2 (9% cos "2L 24 (o(.v i8-- r 4Q; P88? ciA-rAurs-r 48 L I 12 I 94 flows 5'2 54- 9'2.

t .5 charlcfilrildgzm eglg grfpaveo or Clittlorr e5 United States Patent TREATING HYDROCARBON OILS WITH INERT SOLIDS AND GASEOUS HALOGEN. CONTAIN- ING COMPOUNDS Clark E. Adams and Charles N. Kimberlin, Jr., Baton Rouge, La., assiguors to Esso Research and Engineermg Company, a corporation of Delaware Application April 29, 1952, Serial No. 285,018

4 Claims. (Cl. 208-114) This invention relates to a process for treating hydrocarbons and more particularly relates to the conversion of higher boiling hydrocarbons to lower boiling hydrocarbons.

This invention is especially concerned with cracking or conversion of petroleum oil residuums or residual oil obtained when distilling crude petroleum oil to recover distillate fractions such as naphtha, heating oil, gas oil, etc. The residual oil resulting from such distillation is a high boiling hydrocarbon oil which cannot be vaporized at ordinary pressures without cracking the high boiling constituents in the residual oil.

It is known to coke or visbreak heavy residual petroleum oils in the presence of finely divided inert solid particles maintained as a fluidized bed. -In coking, poor quality gasoline or motor fuel is obtained and in visbreaking a small amount of poor quality gasoline and a larger amount of gas oil stock is obtained which gas oil is a relatively poor cracking stock but may be used as feed for a catalytic cracking unit.

According to the present invention heavy residual petroleum oil is contacted with a dense fluidized bed of catalytically inert solid particles in a reaction zone heated to a cracking temperature. At the same time a gaseous or volatile cracking catalyst is passed through the dense fluidized bed to crack the heavy residual oil to motor fuel and other hydrocarbons lower boiling or of lower molecular weight than the hydrocarbons in the heavy residual oil being cracked.

in the drawing the figure represents one form of apparatus adapted to carry out the process of the present invention.

Referring now to the drawing the reference character designates a line for introducing heavy residual petroleum oil and steam or inert gas carrier. The residual oil may be preheated to a temperature of about 500 to 800 F. before being mixed with hot inert finely divided solids introduced into line 10 from standpipe 12.. In some cases the oil without preheating is mixed with the hot solids in which event the solids are heated to a sufliciently high temperature and a sufiicient amount of solids is used to vaporize and crack the oil. The inert solids may comprise sand, pumice, kieselguhr, Carborundum, etc. but preferably are finely divided petroleum coke. The inert solids have a particle size between about 100 and 400 standard mesh or finer. Stated in another way the particle size is such that less than about 20% is 0-20 microns, about 40 to 60% is between 20 and 80 microns and the rest larger than 80 microns. The finely divided inert solids in standpipe 12 are at a temperature between about1000 and 1500 F. The heating of the solids will be hereinafter described in greater detail. The amount of inert solids added to'line 10 from standpipe 12 is about 5.00 to 7000 lbs. per barrel of oil feed, preferably about 1500 to 5000 lbs. per barrel of oil. I

The heavy oil may comprise atmospheric or vacuum residual petroleum oil, reduced or whole petroleum crude oil, tars, pitches, shale oil, heavy cycle oil or virgin gas oils and the like. Heavy residual petroleum oils may have a gravity of about 0 to 20 API and a Conradson carbon of about 5 to 30 wt. percent and an initial boiling point above about 800 F. for atmospheric residua or above about 1050 F. for vacuum residua. When using gas oils or cycle oils the initial boiling point may be about 600 to 800 F.

The mixture of hot inert solids and oil is then passed through line 14 into cracking vessel 16. The mixture is passed into inverted cone 18 having a horizontal grid 22 arranged in its upper end for distributing the solids and oil across the area of the reaction or cracking vessel 16. The inverted cone 18 and grid 22 are preferably arranged in the lower portion of vessel 16 and concentric therewith. The grid 22 is smaller in diameter than the internal diameter of vessel 16 to provide an annular space 24 for. withdrawal of solids from the vessel 16. The superficial velocity of the vapors and gases passing upwardly through the cracking vessel 16 is selected to provide. a dense dry fluidized turbulent bed of solids in Vessel 16 with a level indicated at 28 and a dilute or less dense phase 32 thereabove. The dense fluidized bed supplies heat for the cracking step and also controls the temperatures during cracking. The superficial velocity of the gases and vapors passing upwardly through the dense bed may be between 0.5 and 5 feet per second and when using particle sizes of the range above described.

Instead of introducing the solids and oil as a mixture via line 14, the oil may be introduced via line 14 or another line directly into or onto the dense fluidized bed 26 in vessel 16 and the hot inert solids may be separately introduced into vessel 16 so that mixing of the solids and oil will take place in vessel 16.

The gaseous or volatile catalyst is-added through line 34 to the mixture passing through line 14. However, the gaseous catalyst may be added by a separate line directly to the dense fluidized bed 26 maintained in vessel 16. The gaseous catalyst is any suitable cracking catalyst and may comprise anhydrous AlCl anhydrous FeCl;,, HCl, HBr, HI, Br l vB1 BCl P01 S0 S0 H 8, SOCl C001 HF or mixtures thereof. Instead of a gaseous catalyst, components which form a gaseous catalyst in cracking vessel 16 may be used, such as: hydrogen with the halides, chlorine, bromine or iodine; also HCl, OOCI 'or SOCl may react with iron or alumina in the reactor to produce AlCl or FeC1 In the usual cracking operations a solid catalyst is used which becomes partially deactivated by the deposition of coke thereon and the catalyst must be regenerated by burningwith air before being used again in a cracking step. In the present invention as the catalyst is gaseous, there is no deposition of carbon thereon and no need to regenerate the catalyst. The catalyst may be used on a once through basis and discarded. To recover the gaseous catalyst it is only necessary to scrub the gases separated during fractionation of the cracked products and return the resulting solution to line 34 for recycling to the cracking vessel 16.

The amount of gaseous catalyst used is about 0.05 to 10 lbs. per barrel of oil feed, preferably 0.05 to 1 lb. per barrel.

The temperature during cracking in dense fluidized bed 26 is between about 700 andl F. The cracking is carried out under substantially atmospheric pressure but pressures up to about 200 lbs. per square inch may be used. The cracked vaporous products pass into dilute phase 32 and thence into a gas-solids separating means 36 such as a cyclone separator to separate entrained solids from vaporous products which pass overhead through line 38 and may be further treated as by fractionation to separate desired motor fuel from gas and higher boiling distillates. The separated solids from separator 36 are returned to the dense fluidized bed 26 through dip pipe 42 which normally extends below the level 28 of the dense bed 26. I

- During the cracking of the hydrocarbon oil coke 'or carbonaceous material is formed and deposited onthe coke or other inert particles forming the dense fluidized bed 26 so that the weight and volume of coke is increased. Coke particles are continuously withdrawn from the bottom portion of the dense fluidized bed 26 and passed through a stripping section 44 where the coke particles are stripped of volatile hydrocarbons by stripping gas such as steam introduced through one or more lines 46. The stripped coke particles pass to standpipe 48 provided with one or more aerating lines 52 for supplying aerating gas such as steam to the coke particles in the standpipe to maintain the particles in fluidized form and to produce a hydrostatic pressure at the base of the standpipe. The standpipe 48 as provided with a slide valve 54 for controlling the rate of flow of solids from standpipe 48.

From standpipe 48 the coke particles are introduced into line 56 where they are picked up by an oxidizing gas such as air to form a suspension which is passed through line 58 into the lower portion of a heater or burner vessel 62 for burning part of the coke and to raise the temperature of the rest of the coke and thus supply heat for the process. The bottom portion of vessel 62 is provided with conical inlet chamber 64 and grid member 66 similar to inlet chamber 18 and grid member 22 previously described in connection with cracking vessel 16. The oxidizing gas passing upwardly through burning or heating vessel 62 has a superficial velocity between about 0.5 and feet per second to maintain the coke particles during burning as a dense fluidized turbulent bed 68 having a level designated at 72 and a dilute phase 74 thereabove.

The combustion gases pass from the dilute phase 74 through a gas solids separator such as a cyclone separator 76 to separateentrained solids from the outgoing gas which leaves through outlet 82. As the outgoing combustion gases are at a high temperature, it may be desirable to recover heat therefrom as by passing the gas through heat exchangers, waste heat boilers etc. The recovered heat may be used to preheat the oil feed to the process. The separated solids from separator 76 are returned to the dense bed 68 by means of dip pipe 84 similar to dip pipe 42 above described.

During heating in the burner vessel 62 the temperature of the dense fluidized bed 68 is maintainedbetween about 1000 and 1500 F. The heated coke particles are continuously withdrawn from the lower portion of burner vessel 62, passed through stripping zone 86, if desired, provided with stripping gas inlet lines 88 and into standpipe 12, previously referred to. The standpipe 12 is provided with a slide valve 92 at its bottom portion and also one or more aerating or fluidizing lines 94 for maintaining the particles in a fluidized condition in the standpipe 12 so that hydrostatic pressure is produced at the base of the standpipe. Excess coke made over that required to supply heat for the process is withdrawn from the bottom portion of the burner vessel 62 through line 96. The withdrawn coke may be cooled or quenched and sold as such or used in any desired manner. If insufficient coke is made to supply, the heat for the cracking step, coke or burnable gaseous, solid or liquid fuel may be introduced into burner vessel 62 from an outside source.

Example 1 A residuum representing about 16% bottoms on West Texas crude and having a gravity of 1l.0 API was fed into the bottom of a fluidized bed of sand in a 1.6" internal diameter laboratory reactor heated to an average temperature of about 950 F. The residuum feed rate on sand was about 2 w./hr./w. (weight of residuum per hour per Weight of sand) and steam diluentequivalent cracking feed stock, recycle stock, or fuel stock.

' bulent bed to convert the higher boiling hydrocarbonoil Feed rate, 2 w./hr./w., steam diluent 70 wt. percent on feed. 30 minute cycle, 950 F. reaction temperature.

Added Catalyst 1% H01 on None.

- Feed. Product Distribution:

4, Vol. Per 1 6 1.2. (ls/430 F., Vol. Percent 22.5- 15.5. 430 F.+Btms., Vol. Percent 69 4 74.4.

Gr., APT 9.1-- 13.6. Coke, Wt. Percent 8 4 10.5. C3- Gas, Wt. Percent 3.1 3.2.

It will be noted that in the presence of the homogeneous catalyst I-ICl (1) an enhanced conversion of the residuum to products boiling below 430 F. was obtained and (2) that the selectivity of this conversion to liquid gasoline components was improved. It was-also observed in the analyses of the C components from these'runs that in the presence of the HClcatalyst 7.6 mole percent isobutane was found in the C cut while, no 'isobutane was observed in the absence of theHCl. These results indicate enhanced'isomerization of the products in the presence of the catalyst which result in a higheroctane number gasoline and more valuable products. Example 2 Using the same feed, 'reaetor, and general reaction conditions described in.Example 1, the 16% West Texas residuum, was contacted in the presence and absence; of 0.1 wt. percent iodine on residuum feed. In these runs hydrogen was used as a diluent in amount 'of'5000 cu. ft. per barrel of feed. The iodine was added dissolved in the residuumfeed. The following, tabulation sum man'zes the data obtained. in the presence and inthe absence of iodineat 850. and. 950 F. reaction temper ature. i Feed: 16% West Texas residuum. V l Contact medium: Fluid sand.

Hydrogen diluent, 5,000 c. f./bbl. feed. 30 minute cycles; feed rate 2 w./hr./w. V

Reaction Temp., F J 950 0.1% Iodine on Feed Yes No Yes No Product Distribution: 3 I

04, Vol. Percent 3. 7 1 2. 9 i 3.7 5,0 05/430 F., V01. Percent... 18. 2 '15. 6 26. 3 17. 8 430 F.+Btl11S-, V01. Pereent 71. 4 73. 8 61. 7 69. 7 G12, API -Q 17. 2 15. 8 26.2 '12. 4 Coke, Wt. Percent.. 13. 3 V 11. 5 9. 9 ;-9. 8 (la-G35, Wt. PGIGQDI 1. 6 2.8 4. 3 '4. 6

In the presence of hydrogen and'iodine, enchanc edcon versions and yields of gasoline were obtained at both temperatures. The gravity of the 430 Fri-product formed in the presence of iodine is 'shownlto be higher than when the iodine was omitted and representsa more valuable product for further utilization asa cat-al' "c What is claimed is: 4 I I M 1. A process for converti'n'gihigher boiling hydrocarbons to lower boiling hydrocarbons in the absence of a solid catalyst which needs regeneration; which comprises cont-acting higher boiling: hydrocarbon oil with hot catalytically-inert solid particles in a dense dry fluidized turbulent bed maintained at an'active cracking temperature above about 700 F. and introducing a gaseous halogen-containing catalyst into said dense fluidized turto lower boiling hydrocarbons and recovering' vaporous cracked products overhead.

drocarbons without depositing carbonaceous material on said gaseous catalyst while depositing carbonaceous material on said inert solids.

3. A process for converting residual hydrocarbon oil containing high boiling constituents which cannot be vaporized at ordinary pressures without cracking which comprises introducing such residual hydrocarbon oil into a dense dry fluidized turbulent bed of catalytically-inert finely divided solid particles maintained in a conversion zone at a cracking temperature above about 700 F. and introducing a gaseous halogen-containing catalyst into said dense fluidized bed of inert solids to catalytically crack the residual hydrocarbon oil to lower boiling hydrocarbons without depositing carbonaceous material on said gaseous catalyst while depositing carbonaceous material on said inert solids, continuously withdrawing catalytically-inert solid particles containing carbonaceous material from said dense turbulent fluidized bed, passing the withdrawn inert solid particles to a burning zone wherein at least part of the carbonaceous material is burned from said inert solid particles to raise the temperature of said inert solid particles above the cracking temperature selected for said conversion zone and continuously withdrawing the so-heated inert solid particles from said burning zone and returning them to said conversion zone to supply heat of cracking thereto.

4. A process for converting higher boiling hydrocarbons to lower boiling hydrocarbons in the absence of a solid catalyst which needs regeneration, which comprises contacting higher boiling hydrocarbon oil with hot catalytically-inert solid particles in a dense dry fluidized turbulent bed in a conversion zone maintained at an active cracking temperature above about 700 F. and introducing a gaseous halogen-containing catalyst into said dense fluidized turbulent bed to convert the higher boiling hydrocarbon oil to lower boiling hydrocarbons, removing vaporous cracked products overhead, separating gaseous halogen-containing catalyst from the vaporous cracked products and recycling such catalyst to said conversion zone.

References Cited in the file of this patent UNITED STATES PATENTS 1,971,190 Lelgemann Aug. 21, 1934 2,291,588 Kalichevsky et al. July 28, 1942 2,388,055 Hemminger Oct. 30, 1945 2,407,052 Bailey et a1. Sept. 3, 1946 2,428,715 Marisic Oct. 7, 1947 

1. A PROCESS FOR CONVERTING HIGHER BOILING HYDROCARBONS TO LOWER BOILING HYDROCARBONS IN THE ABSENCE OF A SOLID CATALYST WHICH NEEDS REGENERATION, WHICH COMPRISES CONTACTING HIGHER BOILING HYDROCARBON OIL WITH HOT CATALYTICALLY-INERT SOLID PARTICLES IN A DENSE DRY FLUIDIZED TURBULENT BED MAINTAINED AT AN ACTIVE CRACKING TEMPERATURE ABOVE ABOUT 700*F. AND INTRODUCING A GASEOUS HALOGEN-CONTAINING CATALYST INTO SAID DENSE FLUIDIZED TURBULENT BED TO CONVERT THE HIGHER BOILING HYDROCARBON OIL TO LOWER BOILING HYDROCARBONS AND RECOVERING VAPOROUS CRACKED PRODUCTS OVERHEAD. 